1. Field of the Invention:
The present invention relates to a door gear motor operator.
More particularly, the present invention relates to an independent band spring door gear motor operator.
2. Description of the Prior Art:
Gear motor operators can be adapted to most independent push up band spring doors. By the use of gear motor operators, the strenuous task of manually lifting and pulling down the door is eliminated.
On larger doors, such as bay doors, which use torsion spring axles, a coil spring is incorporated inside the axle pipe. A shaft is welded to the inside of the pipe and protrudes through the end plate and is powered by a chain and sprocket arrangement. This results in the turning of the axle pipe which lifts and lowers the door, as required.
In solution, the U.S. Pat. No. 1,943,371 to Cross relates to end locks for fire doors of the rolling shutter type.
When automatic door openers are provided on doors, such as garage doors it has found to be undesirable to provide a key locking system for the door wherein the door is mechanically locked on operation of the key. This feature has become more undesirable when the automatic door opener is a radio controlled automatic door opener. The reason for the undesirable provision of a key locking means is that once the door is key locked the automatic door opener can be accidentally or unwantingly placed in operation to open the door. If this occurs, then the electric motor used to open the door become locked and thus the motor draws a stalling current. This current is sufficient to burn out the motor and as a consequence initiate a fire.
The U.S. Pat. No. 4,452,292 to Leivenzon et al. relates to an automatic opening means for a door, and a key locking facility which mechanically locks the door in a closed position.
In solution, the U.S. Pat. No. 4,721,146 to Wardlaw relates to driving mechanisms permitting the safe operation of the door in either the manual drive or motor drive mode.
Rolling doors may be constructed as exemplified by the U.S. Pat. No. 2,820,516 and include operating mechanisms as exemplified by the U.S. Pat. Nos. 3,637,004, 3,853,167 and 2,934,139.
To operate roller doors by means of chain and sprocket mechanisms are not very satisfactory in that they require periodic service, are noisy to operate, and require regular lubrication.
To control the operation of the roller door or shutter by electrical means, two such electrically operated mechanisms are described in the Australian Pat. Application Nos. AUA 30718/77 in the name of B.W.N. Industries PTY. LTD. and 44163/79 in the name of Byrne and Davidson Doors (NSW) PTY. Limited.
In solution, the U.S. Pat. No. 4,392,392 to Perisic et al. relates to the operating mechanism by which the door or shutter curtain can be wound onto or unwound from its supporting drum wheels so as to open and close same.
The electric motor and its associated gear train rotates, as a body, simultaneously with the door curtain supporting drum wheels and by having the electric motor housed within the core of the door curtain.
In the art of garage door operator mechanisms it has been necessary for an installer of the operator to accurately adjust the upper and lower limit stops of the door so that power to the driving motor can be removed when the door reaches those positions. Usually this adjustment involves correctly locating limit stop switches on the door frame in the door opened and door closed positions so that when the door reaches those positions the driving motor can be switched off. Alternatively, screw threaded adjustments have been provided which are arranged on a movable part of an operator mechanism so as to switch off the fixed position limit switch of the respective opened and closed positions. A typical example of such operator mechanism is disclosed, for example, in the Australian Pat. No. 528,744.
Other forms of operators which are used for "tilt-up" or "lift-up" doors are disclosed, for example, in U.S. Pat. Nos. 3,439,727 and 4,107,877. U.S. Pat. No. 3,439,727 discloses a chain drive system. The U.S. Pat. No. 4,107,877 uses a similar carriage member, but instead of having a chain drive it has a screw thread which rotatably and screw threadably engages with the carriage.
In both U.S. Pat. No. 3,439,727 and the U.S. Pat. No. 4,107,877 for the "lift-up" or "tilt-up" doors, complicated adjusting means are provided for the setting of the opened and closed positions of the door so that power to the motor can be removed when the door reaches those positions.
In solution, the U.S. Pat. No. 4,706,727 to Leivenson et al. relates to a door operator for use in domestic garage doors of the "roll-up" type or the "tilt-up" or "lift-up" type.
In solution, the U.S. Pat. No. 3,739,832 to Sivin relates to an overhead grille capable of emergency ascending movement from its closed position so as to provide an emergency or exit opening beneath its lower edge.
It has been the practice heretofore in raising and lowering heavy closures to employ counterbalancing devices for facilitating movement thereof. Such devices in the art have torsional springs that are wound up as the closure descends, allowing setting up an increased potential force when the closure reaches its ultimate descent. This force assists in lifting the closure upon manually raising the same, the spring unwinding with decreasing force as the closure is rolled upon its drum. Counterbalancing devices employing torsional type springs, however, are unsatisfactory, particularly in view of the heavy steel wire that is required and also in view of the end connections therefor. Attempts have been made to overcome these disadvantages by utilizing the expansive and contractive force of springs but these have also been unsuccessful.
In solution, the U.S. Pat. No. 2,543,711 to Schultz relates to vertically movable closures for door and window openings.
The following U.S. patents disclose structures known in the relevant art: U.S. Pat. No. 3,595--May 25, 1844, U.S. Pat. No. 330,956--Nov. 24, 1885, U.S. Pat. No. 1,022,939--Apr. 9, 1912, U.S. Pat. No. 2,513,042--Jun. 27, 1950, U.S. Pat. No. 2,545,400--Mar. 13, 1951, U.S. Pat. No. 2,906,323--Sept. 29, 1959, U.S. Pat. No. 3,065,785--Nov. 27, 1962, and U.S. Pat. No. 4,010,790--Mar. 8, 1977.
In solution, the U.S. Pat. No. 4,301,851 to Gitkin relates to a combined roller shutter and awning for a door assembly such as a sliding glass door arrangement providing access between the interior of a building.
Numerous innovations for door motor operators have been provided in the prior art that are adapted to be used. Even though these innovations may be suitable for the specific individual purposes to which they address, they would not be suitable for the purposes of the present invention as heretofore described.